1. Field of the Invention
The present invention relates to a file device and binders to be used for such file device. More particularly, the present invention pertains to a file device for filing thin sheets of recording medium, such as photographic pictures, slides, medical specimen plates, floppy discs and the like. The present invention further pertains to components to be used in such file device.
2. Description of the Prior Art
The Japanese patent application Sho 63-241935 filed on Sept. 27, 1988 and disclosed for public inspection on Mar. 29, 1990 under the disclosure number Hei-02-089699 discloses a file sheet adapted for filing thin recording sheets such as photographic slides. The file sheet is made of a thin plastic sheet formed with recesses adapted for receiving the slides. A plurality of such file sheets are bound in suitable binding covers with photographic slides fitted to the recesses of the sheets or that the slides are filed in a readily accessible manner.
In binding such file sheets, file covers having binding rings provided at appropriate spacings may be used. The file sheets may then be formed along an edge portion with binding holes with spacings equal to the spacings of the binding rings so that the binding rings are fitted to the binding holes in the file sheets. This type of file sheet binding device is advantageous in that the file sheets can be added as desired. It should however be noted that in order to bind an additional file sheet the rings are at first opened and the file sheet is engaged at the binding holes with the rings thus opened. Thereafter, the rings are closed to hold the file sheet together with previously bound file sheets. Thus, binding an additional file sheet requires a troublesome task.
Another problem encountered in the aforementioned sheet binding device is that turning over the file sheets is not convenient. More specifically, in this type of binding device, the binding rings are generally of a large size so that a large number of file sheets can be accommodated. The binding rings of such large size have a tendency of making turning over the file sheets difficult because the file sheet may have a tendency of sticking to the binding rings by being inclined with respect to the row of the binding rings.